^1,2,3Fanny CATTANI,²Barbara A. COHEN,⁴Cameron M. MERCER,⁵Agnes J. DAHL
Meteoritics & Planetary Science 58, 591-611 Open Access Link to Article [doi: 10.1111/maps.13960]
¹The Catholic University of America, Washington, DC, USA
²Solar System Exploration Division, NASA Goddard Space Flight Center, Greenbelt, Maryland, USA
³Center for Research and Exploration in Space Science and Technology, NASA/GSFC, Greenbelt, Maryland, USA
⁴U.S. Geological Survey, Geology, Geophysics, Geochemistry Science Center, Denver, Colorado, USA
⁵Department of Earth Sciences, University of Gothenburg, Goteborg, Sweden
Published by arrangement with John Wiley & Sons

Several laboratories have been investigating the feasibility of in situ K-Ar dating foruse in future landing planetary missions. One drawback of these laboratory demonstrations isthe insufficient analogy of the analyzed analog samples with expected future targets. Wepresent the results obtained using the K-Ar laser experiment (KArLE) on two old and K-poorchondritic samples, Pułtusk and Hvittis, as better lunar analogs. The KArLE instrument useslaser ablation to vaporize rock samples and quantifies K content by laser-induced breakdownspectroscopy (LIBS), Ar by quadrupole mass spectrometry (QMS), and ablated mass by laserprofilometry. We performed 64 laser ablations on the chondrites to measure spots with a rangeof K2O and Ar content and used the data to construct isochrons to determine the chondriteformation age. The KArLE isochron ages on Pułtusk and Hvittis are 5059892 Ma and4721793 Ma, respectively, which is within the uncertainty of published reference ages, andinterpreted as the age of their formation. The uncertainty (2σ) on the KArLE ages obtained inthis study is better than 20% (18% for Pułtusk and 17% for Hvittis). The precision, whichcompares our obtained ages to the reference ages, is also better than 20% (11% for Pułtuskand 4% for Hvittis). These results are encouraging for understanding the limits of thistechnique to measure ancient planetary samples and for guiding future improvements to theinstrument.

¹Edward D. Young,²Anat Shahar,¹Hilke E. Schlichting
Nature 616, 306-311 Link to Article [DOI https://doi.org/10.1038/s41586-023-05823-0]
¹Department of Earth, Planetary, and Space Sciences, University of California Los Angeles, Los Angeles, CA, USA
²Carnegie Institution for Science, Earth and Planets Laboratory, Washington, DC, USA

We currently do not have a copyright agreement with this publisher and cannot display the abstract here

¹Martin R. LEE,¹Cameron FLOYD,¹Pierre-Etienne MARTIN,²Xuchao ² A. FRANCHI,¹Laura JENKINS,¹Sammy GRIFFIN
Meteoritics & Planetary Science (in Press) Open Access Link to Article [https://doi.org/10.1111/maps.13978]
¹School of Geographical and Earth Sciences, University of Glasgow, Glasgow G12 8QQ, UK2School of Physical
²Sciences, Open University, Milton Keynes MK7 6AA, UK*Corresponding author.Martin R. Lee, School of Geographical and Earth Sciences, University of Glasgow, Glasgow G12 8QQ, UK
Published by arrangement with John Wiley & Sons

LaPaz Icefield (LAP) 02239 is a mildly aqueously altered CM2 carbonaceouschondrite that hosts a xenolith from a primitive chondritic parent body. The xenolithcontains chondrules and calcium- and aluminum-rich inclusions (CAIs) in a very fine-grained matrix. The chondrules are comparable in mineralogy and oxygen isotopiccomposition with those in the CMs, and its CAIs are also mineralogically similar to the CMpopulation apart for being unusually small and abundant. The presence of serpentinedemonstrates that the xenolith has been aqueously altered, and its phyllosilicate-rich matrixhas a comparable oxygen isotopic composition to the matrices of CM meteorites. Thexenolith’s chondrules lack fine-grained rims, whereas the xenolith itself has a fine-grainedrim that is petrographically and chemically comparable with the rims on coarse grainedobjects in LAP 02239 and other CM meteorites. These properties show that the xenolith’sparent body was formed from similar materials to the CM parent body(ies). Following itslithification by aqueous alteration, a piece of the xenolith’s parent body was impact-ejected,acquired a fine-grained rim while free-floating in the protoplanetary disc, then was accretedalong with rimmed chondrules and other materials to make the LAP 02239 parent body.Subsequent aqueous processing of the LAP 02239 parent body altered the fine-grained rimson the xenolith, chondrules, and CAIs. The xenolith shows that the timespan of geologicalevolution of carbonaceous chondrite parent bodies was sufficiently long for some of them tohave been aqueously altered before others had formed.INTRODUCTIONThe Mighei-like (CM) carbonaceous chondrite (CC)meteorites have close spectroscopic affinities to C-complexasteroids (Burbine,2016) and so likely sample one or moreof them. The parent body(ies) of the CMs were formed bythe accretion of relatively coarse-grained objects (i.e.,chondrules and calcium- and aluminum-rich inclusions[CAIs]) together with fine-grained material that formsthe enclosing matrix (Barber,1981; McSween Jr. &Richardson,1977). The chondrules and other coarse-grainedobjects typically have fine-grained rims that they acquiredwhile free-floating in the protoplanetary disc (Hanna &Ketcham,2018; Metzler et al.,1992). The constituents of thecoarse-grained objects, fine-grained rims and matrix(anhydrous silicates, metal, sulfides, oxides, and amorphousmaterials) were partially to completely altered by parentbody aqueous activity at~4563 Ma (Bunch & Chang,1980;Fujiya et al.,2012; McSween Jr.,1979a,1979b). Theresultant secondary minerals are volumetrically dominatedby phyllosilicates that are intergrown with carbonates,oxides, and sulfides (Barber,1981; Bunch & Chang,1980;Fuchs et al.,1973;Howardetal.,2009,2011,2015;Leeet al.,2014; Tomeoka & Buseck,1985;Trigo-Rodrıguezet al.,2019; Zolensky et al.,1993).TheCMsareclassifiedby petrologic type/subtype using various properties thatMeteoritics & Planetary Science1–16 (2023)doi: 10.1111/maps.139781Ó2023 The Authors.Meteoritics & Planetary Sciencepublished by Wiley Periodicals LLC on behalf of The Meteoritical Society.This is an open access article under the terms of theCreative Commons AttributionLicense, which permits use,distribution and reproduction in any medium, provided the original work is properly cited.

¹K.Righter et al.(>10)
Meteoritics & Planetary Science (in Press) Link to Article [https://doi.org/10.1111/maps.13973]
¹NASA Johnson Space Center, Houston, Texas, USA
Published by arrangement with John Wiley & Sons

NASA’s OSIRIS-REx spacecraft collected samples from carbonaceous near-Earth asteroid (101955) Bennu on October 20, 2020, and will deliver them to the Earth on September 24, 2023. The samples will be processed at the NASA Johnson Space Center (JSC), where most of the sample collection will be subsequently curated in a new cleanroom suite. The spacecraft collected loose regolith two ways: in a bulk sample chamber capable of holding up to 2 kg, and on industrial Velcro “contact pads” intended to collect small particles at the surface. Included in the JSC collection will be the bulk sample, the contact pads, contamination-monitoring witness plates, and supporting hardware. Planning for the curation of the samples and hardware started at the earliest phase of proposal development and continued in parallel with project development and execution. Because a major mission goal is characterization of organic compounds in the Bennu samples, extra effort was spent in the design stage to ensure a clean curation environment. Here, we describe the preparations to receive the sample, including the design, construction, outfitting, and monitoring of the cleanrooms at JSC; the planned recovery of the sample-containing capsule when it lands on Earth; and the approach to characterizing and cataloging the samples. These curation efforts will result in the distribution of pristine Bennu samples from JSC to the OSIRIS-REx science team, international partners, and the global scientific community for years to come.

¹Secana P. GOUDY,¹Myriam TELUS,²Brendan CHAPMAN
Meteoritics & Planetary Science (in Press) Open Access Link to Article [https://doi.org/10.1111/maps.13969]
¹Earth and Planetary Sciences, University of California, Santa Cruz, Santa Cruz, California, USA2School of Earth and Space Exploration, Arizona State University, Tempe, Arizona, USA
²Earth and Planetary Sciences, University of California, Santa Cruz, CA 95064, USA
Published by arrangement with John Wiley & Sons

We examined H4 chondrites Beaver Creek, Forest Vale, Quenggouk, Ste. Marguerite, and Sena with the electron backscatter diffraction (EBSD) techniques of Ruzicka and Hugo (2018) to determine if there is evidence for shock metamorphism consistent with the previously inferred histories of their early impact excavation or lack thereof. We find that all samples have EBSD data consistent with a history of synmetamorphic impact shock (i.e., shock during thermal metamorphism), followed by postshock annealing. Petrographic analysis of Sena, Quenggouk, and Ste. Marguerite found exsolved Cu and irregular troilite within Fe metal, features consistent with shock metamorphism. All samples have a spatial variability in grain deformation consistent with shock processes, though Forest Vale, Quenggouk, and Ste. Marguerite may have relict signatures of accretional deformation as indicated by variability in their olivine deformation metrics. Within the context of previous workers’ geochemical observations, a more complex history is inferred for each sample. The “slow-cooled” samples, Quenggouk and Sena, were subject to synmetamorphic shock without excavation and annealed at depth. The same is true of the “fast-cooled” samples, Beaver Creek, Forest Vale, and Ste. Marguerite. However, after annealing, these rocks were excavated by a secondary impact or impacts around 5.2–6.5 Ma post-CAI formation and were left to cool rapidly on the surface of the H chondrite parent body. These interpreted histories are best compatible with a model of an impact-battered but intact onion shell for the earliest history of the H parent body. However, the EBSD evidence does not preclude a parent body disruption after 7 Ma post-CAI formation.

¹Yves Marrocchi,¹Thomas Rigaudier,¹Maxime Piralla,¹Laurette Piani
Earth and Planetary Science Letters 611, 118151 Link to Article [https://doi.org/10.1016/j.epsl.2023.118151]
¹Université de Lorraine, CNRS, CRPG, UMR 7358, Nancy, France
Copyright Elsevier

The conditions and environments in which hydrated phases in unequilibrated meteorites formed remain debated. Among carbonaceous chondrites, Mighei-type chondrites (CMs) display a large range in the degree of aqueous alteration, and thus record different stages of hydration and alteration. Here, we report the bulk H, C, and N contents, H and C isotopic compositions, and thermogravimetric signatures of the most- and least-altered CMs known so far, Kolang and Asuka 12236, respectively. We also report in-situ SIMS measurements of the hydrogen isotopic compositions of water in both chondrites. Compared to other CMs, Asuka 12236 has the lowest bulk water content (3.3 wt.% H2O) and the most D-rich water and bulk isotopic compositions (δD = 180‰ and 280‰, respectively). Combined with literature data, our results show that phyllosilicate-bearing CMs altered to varying degrees accreted water-ice grains with similar isotopic compositions. These results demonstrate that the hydrogen isotopic variations in CM chondrites (i) are not controlled by secondary alteration processes and (ii) were mostly shaped by interactions between the protoplanetary disk and the molecular cloud that episodically fed the disk over several million years. The minimally altered CM chondrites Paris and Asuka 12236 display peculiar, D-rich, hydrogen isotopic compositions that imply the presence of another H-bearing component in addition to insoluble organic matter and phyllosilicates. This component is most likely the hydrated amorphous silicates that are ubiquitous in these chondrites. CM bulk H and O isotopic compositions are linearly correlated, implying that (i) amorphous silicates in CM matrices were already hydrated by disk processes before the onset of CM parent-body alteration, and (ii) the quest for a hypothetically water-free CM3 is illusory.

¹Shui-Jiong Wang,²Shi-Jie Li,³Yangting Lin,¹Si-Zhang Sheng
Geochimica et Cosmochimica Acta (in Press) Link to Article [https://doi.org/10.1016/j.gca.2023.04.004]
¹State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences (Beijing), Beijing 100083, China
²Center for Lunar and Planetary Sciences, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, China
³Key Laboratory of Earth and Planetary Physics, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing, China]
Copyright Elsevier

We present high-precision mass-dependent nickel isotopic data for a comprehensive suite of achondrites and lunar rocks, providing key insights into the early planetary differentiation and Earth-Moon system formation. The primitive achondrites display high Ni contents and invariant Ni isotopic compositions. Incomplete core-mantle differentiation in primitive achondrite parent bodies resulted in the retention of metal in the mantle, which dominated the Ni budget and accounted for the bulk chondritic Ni isotopic values. The highly reduced differentiated achondrites, aubrites and an ungrouped achondrite (NWA 8409), have variable, and extremely light Ni isotopic compositions. Acid leaching experiments demonstrate that the sulfides are a significant host of light Ni isotopes in aubrites. The most extreme Ni isotope values of aubrites may be due to large Ni isotope fractionation accompanied by silicate-sulfide-metal separation during differentiation of the parent bodies, and subsequent global disruptive collision and reassembly with variably high proportions of sulfides enriched in the mantle. The howardite-eucrite-diogenite (HED) meteorites show Ni isotopic variations that are positively correlated with Ni/Co ratios, a feature that cannot be produced by igneous differentiation. Late accretion of high-Ni and high-Ni/Co chondritic materials after core formation of their likely parent body, Vesta, could have accounted for this correlation. Thus, the primitive silicate mantle of Vesta may have sub-chondritic Ni isotopic compositions, implying possible Ni isotope fractionation during core-mantle differentiation of small planet bodies. The lunar breccia meteorites have homogenously chondritic Ni isotope values, together with their high Ni/Co of bulk rock and metals therein, suggesting impact contamination. Lunar basalt meteorites have low Ni/Co ratios and are systematically isotopically lighter than the breccias, displaying a positive correlation between Ni isotope value and Ni/Co ratio, as that seen in the HEDs. Therefore, the Ni isotopic systematics in lunar rocks also indicates the effect of late accretion, with the primitive lunar mantle having sub-chondritic Ni isotope values. This implies that the Moon-forming impactor, Theia, was likely an aubrite-like differentiated planetary body whose mantle was enriched in light Ni isotopes. We suggest that there was significant Ni isotope fractionation between core and mantle during differentiation of early formed small planetary bodies, but this signature can be obscured by late accretion in the bulk achondrite records.

^1,2Toshimori Sekine,²Tsubasa Tobase,³Youjun Zhang,⁴Ginga Kitahara,⁴Akira Yoshiasa,⁵Tomoko Sato,⁶Takamichi Kobayashi,⁷Akihisa Mori
American Mineralogist 108, 686-694 Link to Article [http://www.minsocam.org/msa/ammin/toc/2023/Abstracts/AM108P0686.pdf]
¹Center for High Pressure Science and Technology Advanced Research, Shanghai 201203, China
²Graduate School of Engineering, Osaka University, Suita 565-0871, Japan
³Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, China
⁴Graduate School of Science and Technology, Kumamoto University, Kumamoto 860-8555, Japan
⁵Department of Earth and Planetary Systems Science, Hiroshima University, Higashi-Hiroshima 739-8526, Japan
⁶National Institute for Materials Science, Tsukuba 305-0044, Japan
⁷Department of Mechanical Engineering, Sojo University, Kumamoto 860-0082, Japan
Copyright: The Mineralogical Society of America

Heavy meteorite impacts on Earth’s surface produce melt and vapor that are quenched rapidly and
scattered over wide areas as natural glasses with various shapes and characteristic chemistry, which
are known as tektites and impact glasses. Their detailed formation conditions have long been debated
using mineralogical and geochemical data and numerical simulations of impact melt formations. These
impact processes are also related to the formation and evolution of planets. To unravel the formation
conditions of impact-induced glasses, we performed shock recovery experiments on a tektite. Recovered samples were characterized by X-ray diffraction, Raman spectroscopy, and X-ray absorption fine
structure spectroscopy on the Ti K-edge. Results indicate that the densification by shock compression
is subjected to post-shock annealing that alters the density and silicate-framework structures but that
the local structures around octahedrally coordinated Ti ions remain in the quenched glass. The relationship between the average Ti-O distance and Ti K pre-edge centroid energy is found to distinguish the
valance state of Ti ions between Ti4+ and Ti3+ in the glass. This relationship is useful in understanding
the formation conditions of impact-derived natural glasses. The presence of Ti3+ in tektites constrains
the formation conditions at extremely high temperatures or reduced environments. However, impact
glasses collected near the impact sites do not display such conditions, but instead relatively mild and
oxidizing formation conditions. These different formation conditions are consistent with the previous
numerical results on the crater size dependence.

¹George L. Carson,¹Lindsay J. McHenry,²Brian M. Hynek,¹Barry I. Cameron, ¹Chase T. Glenister
American Mineralogist 108, 637-652 Link to Article [http://www.minsocam.org/msa/ammin/toc/2023/Abstracts/AM108P0637.pdf]
¹Department of Geosciences, University of Wisconsin-Milwaukee, 3209 N. Maryland Avenue, Milwaukee, Wisconsin 53211, U.S.A.
²Laboratory for Atmospheric and Space Physics, University of Colorado Boulder, 1234 Innovation Drive, Boulder, Colorado 80303, U.S.A.
Copyright: The Mineralogical Society of America

Iceland’s Námafjall geothermal area exhibits a range of alteration environments. Geochemical and
mineralogical analyses of fumaroles and hot springs interacting with Holocene basaltic lavas at Hverir,
and with Pleistocene hyaloclastites atop nearby Námaskarð hill, reveal different patterns of alteration
depending on water-rock ratio, degree of oxidation, and substrate composition and age. The focus of
this study is on the mineral deposits at and near hot springs at Hverir and Námaskarð. Surface samples,
and samples collected from shallow pits in the alteration aprons adjacent to hot springs, were analyzed
by X-ray diffraction (XRD) and X-ray fluorescence (XRF) to constrain the differences in composition
with both distance and depth. Fluids were analyzed in the field for their environmental parameters and
sampled for cation and anion analysis. Fluid analyses revealed uniformly acidic conditions but with
site-to-site variation in other parameters such as temperature, salinity, and conductivity. Solid phases
identified include amorphous silica, pyrite, elemental sulfur, and kaolinite in the muds, surrounded by
Fe2+-sulfate and then Fe3+-sulfate efflorescence, following a redox gradient pattern involving the oxidation of sulfur and then iron with increasing distance. Shallow pits excavated near two Námaskarð hot
springs reveal a shallow oxidation front, with sulfide-rich materials below a thin surface of sulfates and
elemental sulfur. Silica phases include amorphous silica and quartz. Quartz likely reflects diagenetic
maturation of earlier-formed amorphous silica, under surface hydrothermal conditions.
The high iron content of the substrate basalt and the prevalence of Fe-sulfates and Fe-oxides among
the alteration products make this geothermal area an especially useful analog for potential martian
hydrothermal environments. In particular, these sulfate-rich deposits adjacent to volcanic, acidic hot
springs could provide a helpful comparison for sulfur-rich soils in the Columbia Hills on Mars, where
some of the same minerals have been identified (e.g., ferricopiapite) or inferred (e.g., rhomboclase).

¹Christopher T. Adcock,¹Elisabeth M. Hausrath,²Elizabeth B. Rampe,³Hexiong Yang,³Robert T. Downs
American Mineralogist 108, 430-438Link to Article [http://www.minsocam.org/msa/ammin/toc/2023/Abstracts/AM108P0430.pdf]
¹Department of Geoscience, University of Nevada, Las Vegas, 4505 S. Maryland Parkway, Las Vegas, Nevada 89154-4010, U.S.A.
²NASA Johnson Space Center, 2101 E NASA Parkway, Houston, Texas 77058, U.S.A. 3
Department of Geosciences, University of Arizona, 1040 East 4th Street, Tucson, Arizona 85721-0077, U.S.A.
Copyright: The Mineralogical Society of America

Investigations of planetary processes using phosphate minerals often focus on igneous, recrystallized, or potentially metasomatized minerals, likely as a result of the minerals commonly available for
study within meteorites and lunar samples. However, Mars is a relatively phosphorus-rich planet and
possesses abundant evidence of past aqueous surface interactions. Therefore, secondary phosphate
phases may be important on the martian surface. Giniite [Fe2+Fe4
3+(PO4)4(OH)2·2H2O] is a secondary
phosphate mineral that has been suggested as a potentially significant phase at locations in Gusev Crater
and Meridiani Planum on Mars. Although relatively rare as a natural mineral on Earth, giniite has gained
attention as an important mineral in industry and technology, especially the lithium battery industry,
and the ferrian version of the mineral is often synthesized. This suggests giniite may be important as
an in situ resource utilization (ISRU) target for future extended human missions to Mars. Despite this,
there are few data available on the natural mineral and the last characterization of the structure was
over 40 years ago. There has also been confusion in the literature as to whether giniite is orthorhombic
or monoclinic. In this work we revisit and document the chemistry and crystal structure of natural
giniite from the type locality at the Sandamab pegmatite in Namibia using updated techniques. Our
results refine and update what was previously known regarding the structure and chemistry of giniite
and support the potential of the mineral as a possible martian scientific and resource target for further
study to aid future missions